Continuing from last issue, the Avengers were summoned to a mysterious tropical forest that had appeared near the Arctic Circle by the Wasp. There they were attacked by Ronan the Accuser and the Sentry, who have been holding Captain Marvel hostage. The Sentry had taken over the mind of Goliath/Clinton Barton. The Wasp was knocked out and is found by Yellowjacket (Henry Pym), who had been de-evolved into a primate.

As the Avengers battle the Sentry and Goliath, Ronan explains that he intends to de-evolve the human race so that the Kree can take over the Earth. As the battle rages on, Goliath is defeated and Scarlet Witch and Vision are taken hostage. As prisoners, they begin to express their feelings for each other while elsewhere the primate Yellowjacket protects the Wasp from other primates.

Quicksilver and Rick Jones invade Ronan's base and manage to free Captain Marvel and the others, and counterattack. Ronan is forced to flee when he is contacted by his troops in space, who inform him that the Skrulls have invaded Kree space.

Upon Ronan's departure, the Sentry self-destructs, and the devices maintaining the tropical zone and de-evolving the humans are reversed, with those who turned into primates reverting back to their normal selves.